Research Roundup: A New Protein Linked to Alzheimer’s and Other Highlights

Every week there are numerous scientific studies published. Here’s a look at some of the more interesting ones.

New Protein Linked to Alzheimer’s

Two proteins are traditionally associated with Alzheimer’s disease—amyloid and tau. Amyloid typically occurs early on in the disease while tau is more common toward the end of the disease. Researchers at the RIKENCenter for Brain Science (CBS) haveidentified a new protein that might make the connection between amyloid plaques and tau in Alzheimer’s patients. The protein is called CAPON and was identified in a mouse model of Alzheimer’s disease. They published the research in the journal Nature Communications.

CAPON binds to tau. The CAPON gene is a known risk factor for other psychiatric disorders, which are also common in Alzheimer’s. They discovered an accumulation of CAPON in the hippocampus of their mice. The hippocampus is an important memory center in the brain. And they found CAPON accumulation was present in even larger quantities than amyloid-beta. They also inserted CAPON DNA into one mouse model, causing CAPON to overexpress. These mice had greater neurodegeneration, elevated tau, and shrinkage of the hippocampus.

“The implication is that accumulating CAPON increases AD-related pathology,” stated lead author Shoko Hashimoto. “Although cell death resulting from CAPON can occur through many different pathways, we definitely think this protein is a facilitator between neuroinflammation and tau pathology.”

• A Map of the Most Common Bacterial Pneumonia

Scientists have conducted a global genomic survey of Steptococcus pneumoniae and in their map, found 621 strains across more than 50 countries. The bacteria are the most common cause of bacterial pneumonia and are the biggest cause of infectious disease death in children under the age of five. Although there are vaccines, the broad spread of the bacteria and the variety of strains explains why the disease continues to infect and kill people globally.

• Cells Have a Molecular “Midlife Crisis”

It turns out that although human cells have mechanisms for cellular repair related to longevity, many of those mechanisms stop working after about 50 years of age. Two mechanisms are responsible for about two-thirds of molecular aging in humans—mTOR protein complexes and mitochondrial reactive oxygen species production. Scientists recently found that there are some non-protein-coding genes involved in human aging that are widely present in human cells but not usually in lower organisms. They believe these so-called “dark matter” of the human genome play an important role in “fine-tuning” the molecular aspects of aging.

• Just When You Think You Understand Genetic Translation

Ribosomes read the genetic code in DNA and assemble proteins based on the information there. The code is translated in groups of three “letters,” each group representing an amino acid. But in some cases, in what is called “out-of-frame” translation, if the code is misread by a single letter, it can throw the entire translation process out of whack. For example: “the man saw his new red car” — if the ribosome begins translating it one letter off, the sentence reads, “hem ans awh isn ewr edc ar.” Researchers using advanced microscopy found this type of misreading happens far more often than expected, and in extreme cases, almost half of the proteins assembled use a different reading frame. The result is that DNA often creates thousands of unknown proteins whose function is unknown.

• Whooping Cough Vaccine Losing its Effectiveness

The vaccine for Whooping cough, known as the pertussis vaccine, is generally very effective, but a research study has found that recent outbreaks of the disease are partly related to the vaccine losing its effectiveness over time. Whooping cough is a very contagious, potentially life-threatening respiratory infection caused by the bacterium Bordatella pertussis. The DTaP vaccine, which protects against pertussis, diphtheria, and tetanus, is usually given in five doses between the ages of two months and six years. Part of the reason it is being seen more often is parents aren’t completing their children’s vaccine regimen.

• A Cure for the Common Cold?

Maybe, maybe not. But researchers studying picornaviruses, which includes the rhinoviruses that cause the common cold, as well as enteroviruses, found a new structure that stabilizes a model picornavirus. This was a previously unknown indentation in the surface of the virus where a compound they were studying lodged. The researchers believe it’s possible that drugs could be developed to affect that pocket, making the viruses less likely to mutate.